Can opener stop element



H. A. BERKMAN 2,423,221

CAN OPENER STOP ELEMENT July 1, 1947.

Filed March 4, 1946 /1 Z'iorwqy.

Patented July 1, 1947 UNITED CAN OPENER STOP ELEMENT Herbert A. Berkman, Chicago, 111,, assignor to Zim Manufacturing Company, a corporation of Illinois Application March 4, 194.6, Serial No. 651,734

4 Claims.

In Patent No. 2,258,583, granted on an application filed by me and William S. West, there is disclosed a can opener in which a can to be opened is gripped between a rotatable cutter and an underlying feed wheel carried on a movable arm that shifts the feed wheel toward and away from the cutter; the bead around the top of the can resting on the feed wheel and the cutter extending down through the can end on the inner side of the bead while the can end is being cut out. With that construction, means must be provided to steady the cans and resist the tendency of the cutter and the bead to spread apart and cause the cutting point to drift toward the axis of the can as the can is pulled around against the cutting edge. In the aforesaid patent, to prevent such wandering of the cutting point, a lug is placed on the arm carrying the cutter near the feed wheel and in advance of the cutting point. By giving to the lug the shape of a half frustum of a cone'lying on its flat side against the arm that carries the feed wheel, with the smaller end of the lug nearest the feed wheel, satisfactory results are obtained in the case of round cans whereas, with square or rectangular cans that have straight sides, there is a tendency to mar the cans while cutting out their ends.

ihe primary object of the present invention is to substitute for the frusto conical stop element of the aforesaid patent a means that shall serve its intended purpose in a highly satisfactory manner, without marring the can, regardless of the size or shape of the can.

In the case of round cans a variable stop is needed because of the different radii that cans of different sizes have; but a single fixed stop is sufficient to serve all polygonal cans, regardless of size, because the determining factor is simply the straight sides of such cans. The type of stop that provides the most graduations in adjustments over a considerable range is one that yields, namely, one that is a spring or is spring pressed.

Viewed in one of its aspects, the present invention may be said to have for its object to provide a can opener with stop means that has the desirable characteristic of being yieldable while engaged by a round can and which becomes a fixed stop at times when a polygonal can is being opened.

The various features of novelty whereby the present invention is characterized will hereinafter be pointed out with particularity in the appended claims; but, for a full understanding of the invention and of its objects and advantages, lfQ l'r Eli erence may be had to the following detailed description taken in'connection with the accompanying drawing, wherein:

Figure 1 is a front elevational view of a can opener embodying the present invention in a pree ferred form; Fig. 2 is an end view, looking at the device from a point to the right of Fig. 1; and Figs. 3 and 4 are like sections on line 3-4 of Fig. 1, showing, respectively, a round can and a rectangular or square can in the process of being opened, with the cans indicated in broken lines.

Referring to the drawing, l is .a long arm in the form of a narrow, fiat metal plate standing on edge and provided at one end with suitable means to support the same in a horizontal position for use. Lying against one face of arm I is a second arm 2, also in the form of a metal plate, somewhat narrower and shorter than the first arm, standing on edge. The two arms are connected at their inner or base ends by a hinge pin .3. A rotatable cutter 4 is mounted at the upper edge of arm I, ear the free end, so as to project over the second arm, with its axis extending forwardly and downwardly. On the front side of arm 2, at the free end, is a peripherally toothed or ridged feed wheel 5. This arm is adapted to be shifted up and toward the ri ht, as viewed in Fig. 1, by the lever B, as in the aforesaid patent, until the feed wheel lies directly below and in the rear of the cutter, with its extreme upper portion overlapping the cutter.

It will be seen that arm 2 does not extend substantially beyond the feed wheel at its free end, so that arm 1| has a considerable length thereof lying outwardly from the free end of arm 2. Fastened to arm I, in the exposed area adjacent to the free end, is a, stiff leaf spring bent so as to have end sections 1 and 8, that are in planes parallel to but spaced 'alpart from each other, joined by a more for less diagonal section 9. This spring is vertical, the lower section lying flat against arm I and being fastened thereto by rivets In; section 9 sloping forwardly and upwardly; and section 8 being parallel to but spaced apart from the flat front face of the arm. In actual practice the upper part 8 of the spring stands about a quarter of an inch away from the face of arm I, with its can-engaging face positioned a little forward of the plane of the front side of the feed wheel, and with its extreme upper end reaching to a level above the lowermost point of the cutter.

On the front side of arm 5, with the point of farthest forward projection thereof somewhat 3 below the top of the feed wheel when the latter is up, is a lug II that protrudes a little forwardly past the plane of the rear face of the feed wheel. The lug is preferably a pointed dome-like part formed by pressing the metal of arm I forward.

In the use of the device, the parts being in the positions which they occupy in Fig. 1, a round can, for example, is placed in an upright position against the front or exposed face of the feed wheel, with the usual bead resting on the periphery of the wheel. The lever 6 is then swung in the clockwise direction, shifting arm 2 so as to carry the feed wheel and can up and to the right. Before this step is completed, the cutting edge of the cutter contacts the can end, in the usual way and, during the final movement, punctures the same. The condition of the parts with which the present invention is concerned, is now as illustrated in Fig. 3, A being the can. The can happens to be of such diameter that at the time the can is being gripped and is ready to be turned through rotation of the feed wheel by the usual handl 12, the rim of the can just touches the spring stop and does not yet stress the same. However, when the feed wheel starts to turn, drawing the can rim to and through the cutting point from right to left, the can tends to swing in a direction to press the upper end of the spring back. This swinging movement of the can is resisted by the spring and the displacement of the can held to a minimum. In the case of a larger can, the spring is pushed back somewhat upon the insertion of the can, but still remains clear of the stop, so that it may yield substantially as the can rotates during the cutting out of the can end.

Fig. 1 illustrates a situation wherein a square or rectangular can 3 is being opened. The initial puncture has been made and the can rim is being drawn through the cutting point. It will be seen that the spring has been pushed back into engagement with the stop lug and that the rim of the can is bowed a little, as at b, where it presses against the spring. In other'words, as the can is carried ahead, during the cutting operation, a little wav is formed in the rim and travels along the latter; the part that is bent in passing the stop straightening as soon as the stop is left behind. The can is not marred by this flexing of the rim, nor is the spring in danger of being distorted and given a permanent set on account of being bent so far as to stress it beyond its elastic limit. In other words, a spring which may be used to meet all of the needs of round cans of various sizes, without being overstressed, is protected during the opening of square and rectangular cans without danger of causing damage to the latter cans.

The point of the dome-like stop preferably lies at a, little lower level than the highest point on the feed wheel when the latter is in the raised position shown in broken lines in Fig. 2. Therefore the extreme upper end of the spring, which is the part engaged by the bead on the can when the can is firmly gripped in the device, can bend back a little farther even after the spring engages the stop; thereby reducing the extent to which the bead on a square or rectangular can must flex as the cutting progresses.

While I have illustrated and described with particularity only a single preferred form of my invention, I do not desire to be limited to the precise details thus illustrated and described; but intend to cover all forms and arrangements that come within the definitions of my invention constituting the appended claims.

I claim:

1. In a can opener device, a stationary member in the form of a long narrow plate standing on edge, a cutter on one side thereof, a movable member on said side of the stationary member, a feed wheel on said movable member below said cutter and movable from and toward the latter when the movable member is shifted back and forth, a vertical leaf spring fixed at its lower end Cal to the stationary member at a lower level than the feed wheel and extending upward and away from said side of the stationary member to a level above th lowest point of the cutter, and a projection on the stationary member directly behind the upper end of the spring, the parts being so proportioned and arranged that when the device is empty the spring is spaced apart a considerable distance from the projection and is pressed firmly against the latter by the bead of a straight-sided can inserted in the device.

2. A device as set forth in claim 1, wherein the movable member carrying the feed wheel is a narrow plate lying fiat against the stationary member, andwherein the projection on the sta tionary member extends a little beyond the plane of the outer face of the mo zable member.

3. A device as set forth in claim 1, wherein the upper and lower end sections of the spring are parallel to the adjacent side face of the stationary member and are connected by an intervening straight inclined section.

4. A device as set forth in claim 1, wherein the projection on the stationary member is a small dome-shaped element composed of metal that has been pressed out of the plane of the stationary member.

HERBERT A. BERKMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,074,094 Rush Mar, 16, 1937 2,258,583 Berkman et al Oct. 14, 1941 

